Plumbing, Bilge, Part 5: Manual Bilge Pump, Disassembly and Cleaning

The housing for the Whale Gusher 10 manual bilge pump, disassembled and cleaned

Having cleaned the bronze strum box for the manual bilge pump, I could now focus on the manual bilge pump itself. In this posting I describe my disassembly and cleaning of this pump for Oystercatcher, my Ericson 25.

When I first saw this boat in October 2009, it looked as if her manual bilge pump had not been used in years.

The exterior of the pump was covered with debris from dirt dobber nests, not unlike much of the rest of the boat.

When I returned to the boat for a second visit - this time with a marine surveyor - the owner had cleaned things up a bit. Admittedly, the pump looked better, but appearances can be deceiving.

The owner was eager to demonstrate that he could work the pump handle up and down. This did not mean, however, that the pump itself actually worked. The bilge was dry (because the owner had cleaned it out), so there was no way to tell whether the pump was truly functional.

I did not even bother to experiment with this pump after I bought the boat and transported it to my home. This pump was almost 40 years old. Why not buy a rebuilt kit and bring it back up to a nearly-new condition? That was my thinking.

Just for the record, I took a couple of pictures to remind myself of the appearance of the original configuration.

Then I got to work on the disassembly of the pump. I began by removing the large stainless steel clamp that secured the large, black, neoprene diaphragm.

When I lifted the diaphram, I was able to inspect the interior of the metal housing.

It was full of salt crystals and the white powder associated with galvanic corrosion.

This corrosion was due, I would guess, to the presence of stainless steel screws in the aluminum housing. It's possible, also, I suppose, that the bronze strum box, although distant from the pump, played some part.

After removing the simple inlet valve, I focused on what is known as the "Outlet Valve Plate Assembly."

This thing was wretched looking.

The gasket and valve for this assembly were caked with salt and corrosion, just like the aluminum housing itself.

The neoprene diaphragm was not much better - cleaner but on the verge of cracking due to wear and tear over the years.

After a lot of work with a small screwdriver and some other small instruments I was able to remove most of the salt and corrosion from the aluminum housing. Now I could rebuild the pump. That is the subject of my next posting.

This ends this posting on my disassembly and cleaning of the manual bilge pump for Oystercatcher, my Ericson 25.